<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    * {
        margin: 0;
        padding: 0;
        list-style-type: none;
    }

    html,
    body {
        height: 100%;
    }

    #ul1 {
        display: flex;
        flex-direction: column;
        height: 100%;
        -webkit-box-direction: reverse;
    }

    #ul1 {
        flex: 1;
        text-align: center;
    }

    #ul1 li:nth-child(1) {
        background-color: aqua;
    }

    #ul1 li:nth-child(2) {
        background-color: greenyellow;
    }
    #ul1 li:nth-child(3) {
    background-color: skyblue;
    }
</style>

<body>
    <ul id="ul1">
        <li>001</li>
        <li>003</li>
        <li>003</li>
    </ul>
</body>

</html>